England were crowned the 2020 Women's Six Nations champions after nearest challengers France were held to a shock 13-13 draw by Scotland in Glasgow on Sunday.
France, the 2018 champions, needed to win to ensure the title race would go all the way to next week's concluding round and were on course at 13-6 up with just seven minutes left.
But Scotland wing Rachel Shankland marked her Test debut with a well-taken try before Helen Nelson landed a tough conversion from out on the right to level the scores.
The draw left reigning champions England with an unassailable six-point lead ahead of their November 1 finale against Italy in a tournament which, in common with other major sporting competitions this year, has been interrupted by the Covid-19 pandemic.
Victory away to the Azzurri would give England back-to-back Grand Slams.
Before the coronavirus halted the competition for eight months, England won their opening four games, starting with a hard-fought 19-13 success away to perennial rivals France in Pau.
"We are delighted to have retained the title after four big performances from the team to date," said England women's coach Simon Middleton in a Rugby Football Union statement.
"It's a fitting reward for all the hard work put in earlier this year. We have a big week ahead and the aim is to stay focused on securing the Grand Slam in Italy next weekend."